Rotary orill bit



Qct. 23,1923. R. o. PICKIN ROTARY DRILL BIT Filed July 19. 1920 ROWLAND o. mom, or LOS ans, cannon ICE.

noraar DRILL m.

, Application filed July 19, 1920. Serial No. 397,215..

To all whomz't may concern:

' Be it known that I, ROWLAND O. PICKIN, a subject of the King of Great Britain, and residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Rotary Drill Bit, ofwhich the following is a vfull and clear description, such as will enable others skilled in the art to which it; appertains to make and use the same. 1

My invention relates to improvements in rotary drill bits for the purpose of'drilling holes in the earth, such as oil wells and the like, by the rotary method of drilling.

The,principal object of the invention is to provide a more eflicient and economically constructed bit for drilling holes through a varied formation.

Another object of the invention is the provision of a bit that is less inclined to deviate from a strai ht course.

Another 0 ject of the invention is to provide a bit with a recessed cutting center, to

increase the drilling speed.

Another object of the invention is to provide a bit with a cutting means distributed .so as to maintain a constant and even keenness as the bit wears away.

- Other objects and advantages of the invention will be apparent asit is better understood from the following description,

when considered in connection with the accompanying drawings, illustrating a prep the cavities are ferred embodiment thereof.

0n the drawings:

Fig. 1 is a front sectional elevation of the bit, taken through the center and .on the line 11, Figs. 2, 3 and 4. I

Fig. 2 is a side sectional elevation of the bit, taken' through the center, and on the line 2-2, Figs. 1, 3 and Fig. 3 is a bottom sectional view of the bit taken on the line 33, Figs. 1 and 2.

Fig. 4 is a bottom view of the bit.

'Similar numerals refer tov similar parts throughout the several views.

In Figs. 1, 2, 3, and gt the cutting portion of the bit is indicated by the numeral 10,. .and attached to the upper portion of this framework is the shank 11, upon which is the taper threaded pin 12, Figs. 1 and v The cutting portion 10 of the bit consists of a tapering framework, formed into a plu-,

rality of cutting wings and in'the illustrations two wings 13 and 14 are shown. The

' the framewor bit is made in this manner for the reason that thereis more materialto' be, cut on the outercircumference than towards the center, and'consequentl the bit wears away faster on the outsi e This .also has a tendency to keep .the hole straight, as the high central portion of the hole acts as a guide, and further this central portion is more easily cut away when it comes in contact with the central cutting portion 15 of the bit.

The cutting formed by cavities 16 throughout the bit, wherever the bit comes in contact with'thehole, as it is'worn away in service.

The cavities are formed so as to divide the framework of the bit edges, and in such a manner as to prevent a cavities being on the same level. In the than in the center.'

portion of the bit consists of into a series of cutting I present instance this is accomplished by ar- 1 ranging the cavities in inclined rows, sub stantiallyat right angles with the direction of the bore hole and across the line of travel, with other cavities 16 Fig. 4, parallel to the axis of the bit. these latter being for the purpose offurther reducing the material of the walls of the cavities. This form has the additional advantage-of giving an even distribution of the metal of the framework, and presents little difiiculty in manufacturing.

As an additional cutting means some of shown to be filled with an abrasive as 17, held in position by a filler 18-, Figs. 1, 2 and 3.

Passages 19, Figs. 2,3 and e are provided for flushing out the cuttings. 1

In operating, the bit is turned to the rig t, the lowest ting face rst begins to cut, and as this is gradually worn awa the whole face comes oint 20, Figs. 1 and 2 of the cut-' one is worn in proportion, the wall of each cavity forming a cutting edge successively, until the bit is worn out. bit also cuts away the hole as the drilling progresses. l

It is thought that the invention and many of its attendant advantages will be sumciently understood from the foregoing description, and itwill'be apparent that variousch'a'nges may-be made in the form, con- The center of the sisting of a ting frame containing by cavities, and pro ecting outwardly and struction, and arrangement of the parts without departing from the'spirit and scope of the invention or sacrificing any of its'material advantages, the form herein described being merely a preferred. embodiment thereof.

I claim:

' 1. A rotary drill bit, having a plurality of separate wings, said wings consisting of a framework formed with inwardly extending cavities therein.

2. A rota drill bit, having a plurality of downwar y projecting wings, said wings consisting of a framework formed with inwardly extending cavities therein.

3. A rotary drill bit, having a plurality of flatsided, downwardly projecting wings, said wings consisting of a framework formed with inwardly extending cavities therein.

4. A rotary drill bit, having a plurality of flatsided, downwardly projecting cuttin portions, joined by an intermediate recess cutting portion, all of said portions conframework formed by a series of cavities. i V

5. A rotary drill bit, having a plurality of outwardly and downwardly projecting cutting means joined .by an intermediate recessed cutting means, said means consisting of the walls of cavities formed therein.

' 6. A rotary drill bit, having a plurality of outwardly and downwardly projecting cutting means, joined by an intermediate recessed cutting means, said means consisting of a framework containing a multiplicity of cutting edges, said edges being formed by cavities in said frame.

7. A rotary drill bit, consisting of a cutcutting edges formed downwardly from a central cutting portion, and having )a threaded pin connection.

8. A rotary drill bit, having downwardly projectingtapered cutting wings, said wings consisting of a cutting frame containing a multiplicity of cutting edges formed by cavities.

9. 'A rotary drill bit, having a cutting frame containing a. multiplicity of cutting edges formed by parallel inwardly extending recesses the bit. I

10. A rotary drill bit, having a cutting frame with flat sides, said cutting frame having a multiplicity of parallel cutting edges throughout the cutting portion of the frame, said edges being formed by cavities, and said cavities being filled with abrasive cutting materia 11. A rotary drill bit, having a plurality of flatsided, outwardly and downwardly pro jectin cutting portions joined by an in-' terme iate cutting portion, all of said portions consisting of a cutting frame work,

Bowman 0. rionrn.

till

throughout the cutting portion of ill 

